1. Field of the Invention:
This invention relates to a tufting machine and method of preventing sew through and tagging in producing a tufted product.
2. Description of the Prior Art:
In the past, tufting machines have been produced which move the bills of the loopers or hooks forwardly beyond the needles so as to hold the loops in position for producing chain stitching. U.S. Pat. No. 4,419,944 typically discloses this type of machine. Our application Ser. No. 663,183 also discloses a tufting machine having loopers or hooks which hold the bights of the preceding loops in forward positions as the needles descend for producing chain stitching. In our co-pending application, the needle passes adjacent to the body of its looper and inwardly of a portion of the held preceding loop, linking one loop to the next.
The term "sew through" as used herein, means sewing a loop through a portion of a proceeding loop. The term tagging, as used herein, is the creating of a proceeding longer loop due to the engaging and pulling of a preceding loop as the needle sews a current loop. The problem of tagging and sew through has been with the tufting industry at least since the tufts have been sewn closely to each other in a longitudinal row. This problem has never been solved in an inexpensive and expeditious way, even though efforts have been made to overcome the problem.
U.S. Pat. No. 3,316,867 discloses a tufting machine with a needle inclined to the bedplate for keeping the preceding loops out of the paths of the needles. U.S. Pat. No. 2,975,736, for example, discloses a loop shedder mechanism for preventing tagging, in which the needles project into rearwardly opening grooves extending downwardly from the bedplate to terminate almost at the tops of the loopers. When the yarn loops are released from the grooves, they cannot get back in the needle paths. These prior art patents disclose quite expensive ways of preventing tagging and sew through.